I have TPI gauges in my coupe. I had a tech question when I was installing them and called the company. They put me on the phone with one of the design engineers - everyone was courteous and helpful. About a year after I started driving the car, the tachometer started giving eroneous readings. Hit a bump the tach goes crazy; hit another bump it settles down. I've never called them about that problem, so can't say what the outcome might be. Otherwise, all the other gauges work perfectly and I have no complaints. I like them well enough that bought another set for my roadster, but don't have it running yet.